Bumping gaia.json for 2 gaia revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-2_0/rev/94a38733cf98
Author: Ryan VanderMeulen <ryanvm@gmail.com>
Desc: Merge pull request #24628 from davidflanagan/bug1068986-v2.0

Merge pull request #24204 from davidflanagan/bug1068986

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https://hg.mozilla.org/integration/gaia-2_0/rev/55414e0e86f5
Author: David Flanagan <dflanagan@mozilla.com>
Desc: Merge pull request #24204 from davidflanagan/bug1068986

Bug 1068986: convert MediaFrame to use background-image instead of <img> r=justindarc(cherry picked from commit 5baa82f4abae9ce0d10c92a9ecee8fbc4da74e98)

Conflicts:

	shared/js/media/media_frame.js
	tests/python/gaia-ui-tests/gaiatest/apps/gallery/regions/fullscreen_image.py
Bumping manifests a=b2g-bump